Simon Burns has said he uses the car so he can work on sensitive documents, but the Cabinet Office said ministers can also do so on trains. Photograph: Lewis Whyld/PA

The minister responsible for rail fares is set to continue using an £80,000-a-year chauffeur-driven government car to commute daily between his Essex home and Westminster instead of the cheaper train, a spokeswoman for the Department for Transport (DfT) has said.

Simon Burns MP, the minister of state for transport, sparked anger on Sunday when it emerged he had commandeered one of his department's two pool cars to carry him to and from his constituency home in Chelmsford rather than use the regular and much cheaper 35-minute commuter service to Liverpool Street station.

The DfT, which last week announced above-inflation rail fare increases to the anger of many commuters whose rush-hour trains are heavily overcrowded, confirmed the rail fares minister used the £25,000 chauffeur-driven Toyota Avensis five days a week instead of using the Greater Anglia service, which costs £43.50 return for a first-class ticket. The cost of running the government car, which is largely used by Burns, is more than £300 a day.

When Burns was first asked about the arrangement by the Mail on Sunday, he said he took the car only because he was barred from working on his red box of official ministerial papers on the train for security reasons. But that was contradicted by the Cabinet Office, which said ministers could work on papers in public as long as they ensured sensitive material could not be seen.

The DfT is standing by the minister's decision to be driven to and from work, stressing his lack of a home in the capital, rent on which could be claimed on MPs' expenses. A spokeswoman said: "There are good reasons he uses the car and I suspect that won't change."

A DfT spokesman said: "The minister of state does not have a home in London but uses his commute to work on official papers and so travels in a car provided by the government car service for security reasons. The ministerial code permits ministers to use official cars for home-to-office journeys within a reasonable distance of London when they are working on classified papers."

Burns's use of the chauffeur-driven car was uncovered by Fabian Hamilton, a Labour MP who posed a series of written questions to ministers about the use of the government car service.

Maria Eagle, the shadow transport secretary, said Burns's transport arrangements indicated the Conservative-led government was out of touch with normal rail users.

"No wonder ministers are so out of touch with the eye-watering cost of rail fares when they are spending tens of thousands of pounds of taxpayers' money being driven around all day," she said. "They should get out of their limos and speak to those hard-pressed commuters who have this week seen the cost of their season ticket rocket by hundreds of pounds."

Burns has responsibility for rail pricing strategy, which currently involves shifting the cost of paying for the railways more on to users in order to reduce the amount of government subsidy needed. The average price of a rail season ticket will rise by 4.2% this year.

Rail users said Burns's decision to be driven rather than use the train called into doubt his suitability to be a rail minister and criticised his attempt to justify the car use by saying he could not work on official papers on a train.

"This is a pathetic response," said Christian Wolmar, president of Railfuture, the independent campaign for a better rail network. "Ministers have a long history of taking their red boxes on trains. It also must take him a lot longer to travel by car so he is wasting time as well as taxpayers' money. One has to ask if he is a suitable person to be a rail minister if this is his attitude to our railways."

Neil Skinner, vice-chairman of the Essex Rail Users Federation, said: "It is incredibly disappointing. It is confirmation that the service is not good or reliable enough. If it is not good enough for the rail minister then it is confirmation we are not wrong in complaining about the same thing. This line is overcrowded, unreliable and overpriced."